Shield for carbide feeds in acetylene generators



'May 10, 1932. lRw|N 1,857,456

SHIELD FOR CARBIDE FEEDS IN ACETYLENE GENERATORS Filed May 19, 1927IIVI/ENTOH Patented May 10, 1932 I UNITED STATES HERBERT Gr. IRWIN, OFAMARILLO, TEXAS SHIELD CARBIDE FEEDS IN ACETYLENE GENERATORS Applicationfiled May 19,

This invention relates to splash valves or splash shields and drip ringsadapted to prevent water splashing upon the carbide feed valve orotherwise moisture finding its way to and through the feed opening intothe. carbide hopper of an acetylene generator and thereby clogging thefeed. I

In such devices it is common to use a relatively large metallic tubedepending from the 1 hopper bottom about the feed opening to a shortdistance above the water in the water chamber and through which tubecarbide drops as it is fed from the hopper. The purpose of the tubebeing to shield the feed openmg against moisture and water splash whenthe generator is hauled about. The dripring is usually a fiat bandprojection formed on the hopper bottom about the feed opening in placeof the tube, it is used on the stationary type generator and the purposeof same is to prevent Water that accumulates on the under and slopingside of the hopper bottom running down into the feed opening which wouldsoon clog the feed. In recent years various types of valves have beendesigned for use immediately under the carbide feed in an effort to finda satisfactory means for a portable generator to prevent clogging of thefeed due to moisture causing lime deposit.

While the metallic tube splash shield has been given extensive use, ithas one drawback in that it finally clogs or closes with lime a depositat its lower end obstructing the feeding of carbide. The usual drip ringhas a similar disadvantage in that powders of lime from carbide, depositon the inner wall of the ring creating a means of capillary attractionwhereby some of the water at the lower edge of the drip ring is conveyedupwardly into the feed opening thereby clogging the feed. Other splashshields such as. valves, with which I am familiar give more or lesstrouble due to moisture and lime deposit.

The object of my invention is to provide new and useful improvements insplash shields, splash valves and drip rings for the carbide feed andcarbide passageway in an 5.) acetylene generator.

used in the generator shown in Fig. 8.

1927. Serial No. 192,555.

A further object of my invention is to overcome the usual choking up ofthe carbide feed due to moisture and lime deposit.

A further object of my invention is to prevent an obstructive limedeposit in a passage- 56 way for carbide.

A further object of my invention is to prevent a means of capillarattraction forming in a passagewa for car ide.

A further ob ect of my invention is to pro- 00 vide a splash shield anddrip ring that is self cleaning.

With these and other objects in view, my invention consists in thearrangement, combination and construction of the various parts of myimproved device, as described in the specification, claimed in theclaims, and shown in the accompanying drawings, in which:

Figure 1 is a back view of an acetylene generator with walls cut awayshowing a sectional view of a splash shield constructed in accordancewith my invention, the shield being in closed position.

Figure 2 shows my splash shield mounted on a hopper bottom that may beused in such a generator shown in Fig.' 1, this being an end view of theshield clamping members in open position.

Figure 3 is an end view of the shield clamping members in closedposition.

Figure 1 is a side view of the shield and clamping members in closedposition;

Figure 5 is a side view of'the shield and clamping members in'openposition. 0 Figure 6 shows one way for mounting my splash shield on ahopper bottom, the hopper bottom and shield being in section.

Figure 7 is a view of one of the shield clamping members betterillustrating details 'of structure.

Figure 8 is a view of another style of generator with a portion of thewater chamber and carbide hopper cut awa showing an alternate form inwhich my invention may be accomplished. The splash shield here is shownin longitudinal section.

Figure 9 is a side view of the splash shield bility.

- shoulder b F i re 10 is a view lookin down at the mout of the waterchamber of the generator shown in Fi 8.

Figure 11- 1s a plan view of the outlet end of the carbide hopper of thegenerator shown in Fig. 8.

Figure 12 is a side view of a separable hopper bottom for a stationarygenerator show- 1n my invention in a drip ring.

igure 13 shows an alternate form in which my invention may'be worked outin a dri ring.

Re errin to the accompanying drawings, I have use the letter A toindicate enerally the s lash shield which is of ho ow cylindrical ormand composed of soft rubber havin qualities of toughness and durahengreater strength is required in a shield it may contain one or two pliesof cord or preferably a knitting of seamless tubular form. The shieldhaving plain ends shown in Fig. 9, may be cut to the required lengthfrom rubber tube stock. Certain grades of extra heav inner tube stocksuch as used in motor vehicle tires have been found to servesatisfactoril for the purpose. The shields having bea ed lower endportions shown in Figs. 1, 2, 3, 4, 5 and 6 are preferably formed ofsuitable rubber gum heat treated or cured in molds under pressure as iswell known in the art of rubber article and motor vehicle tiremanufacture.

Referring to Fig. 1, numeral 1, designates the water chamber of anacetylene generator; 2, the carbide hopper; 3, a separable hopper bottomcarrying a rim gasket 5- and clamped between the ho per and waterchamber. A band rin 6, 0 such size as will receive the upper en of thesplash shield is formed integral with the hopper bottom about thecarbide feed opening 7, to provide an annular which the upper end of thesplash shie d may be secured to the hopper bottom with a band clamp 8,see Fig. 6. The shield should be of suflicient length to extend downwardto a short distance above the water level. Ordinarily this wouldconstitute a satisfactory shield against moisture from the hopper bottomand the splashing of water in a. generator for limited portable use,such as hauling the generator on a hand truck in and about the shop. Butwhen the generator is to be mounted on a motor vehicle for extendedservice outside the shop and when it is desirable to haul the generatorfully charged with water, carbide and gas, a manually operated clampingdevice is provided to clamp and close the shield immediately under thecarbide feed valve 9, thus preventing water reaching the feed valve andcarbide outlet 7. This form of clamping device has a square frameconsisting of a pair of relatively long stud bolts 10, forming twoopposite sides and a pair of tube members 10E, forming the other twoopposite sides of lar frame like structures having end portions 11K, and12K. The abutting ends of the bar stock after the bending is complete mabe Welded to make an endless structure ad ing rigidity. The upper sidesof the clamping bars pivot in the tube members 10E and the lower exposedsides 11 and 12 engage the splash shield. The end portions of the barsshould be of such length that when the side portion of the bars aremoved toward each other they will meet immediately and directly underthe carbide outlet 7 so that in closing the shield the pocket madethereby will hold not more than a. mere handful of carbide. By clam ingthe shield directly under the carbide out.et the bending of the wall ofthe shield will be about equal on o posite sides and the clampin barsmay eacli have an equal movement. lso the side portions 11 and 12 shouldswing in parallelism so as to clamp the shield with equal tension alongthe line of engagement. Furthermore the clamping bars should beconnected so that when one is moved back and forth as from open positionto clamping position and back again the other bar will move likewise.And in addition to moving back and forth simultaneously the clampingbars should be provided W1th means whereby they will remain under springtension in either open or closed position. This may be accomplished byadding the fingers 11N, and 12N,and the spiral compression spring 13, toone or both end portions of the clamping bars. Upon reference to Fig. 2it will be seen that these fingers extend between the end portions 11Kand 12K overlapping a short distance. The finger UN is made integralwith the end portion 11K about midway thereof and about right anglesthereto, so that when the bar 11 is in open position the finger willrange in a direction above center of the side portion 12K to a pointmidway between the two end portions of the clamping bars. The projectingend of this finger terminates in an elongated eye cam piece HQ. Thefinger 12N, is made integral with the clamping bar 12 at the upper pivotend of the end portion 12K and the finger inclines downward toward thecenter of the opposite end portion 11K, passing through the eyecam-piece HQ, and overlapping the finger 11N a short distance; Theoverlapping of the fingers serve as a stop limiting the opening movementof the clamping bars. The spring 13 fits loosely about the finger 12Nwhereupon one end seats at the junction of the finger with the endportion 12K of the bar, whlle the opposite end of the spring pressesconstantly against the cam-piece 11Q. A plain washer msty be usedbetween the end of the spring an the cam-piece as a necessary wearingmedium directly engaging the cam. It will be seen that upon moving theclampin bar 11 to closed position the extremity of the finger 11N movesupward carrying its campiece llQ upward to a point above a straight linerunning through the center of the pivots 10E, which position thecam-piece may be referred to as being above center. By reason the finger12N extending through the eye of the cam-piece the extremity of same iscarried upward also above center thus moving the clamping bar 12 toclosed position simultaneously with the bar 11. The pressure of thespring 13 on the lower side of the cam-piece in pos1tion above center isapplied to the clampin bars through the medium of the fingers. 11 12Nand pivots 10E, thus holdin the clamping bars in closed position, 0ampingand closing the shield A as shown in Figs. 1, 3 and 4. By movingthe clamping bar 11 to open position, (see Fig. 2) the fingers andcam-piece are brought downward to a position below center, WhlChposition the pressure of the spring applies to push the clamping barsapart. In less words, the fingers 11N, 12N, cam-piece HQ,

and spring 13 may be described as means for gearing the clamping bars 11and 12 together, reversing the pressure of the spring upon the pivots ofthe bars for holding same in either open or closed position. The sidecontact of the fingers as will be seen in Fig. 2 serve to stop theclamping bars in open position. An eye 15 is provided on the lower endof the portion 11K of clamping bar 11 for connection with a crank 17through the medium of the link 16, see Fig. 1. The crank 17 is securedto the inner end of a rock shaft 18, which latter extends outward of thewall of the water chamber 1 through a suitable tubular bearing andpacking gland not shown. The outer end of the rock shaft terminates inan upright handle 19, by which the operator may move the shield clampingbars to either open or closed position at will. As a safety means toprevent undue gas pressure on wall of the shield above the clamping barsin case the operator fails to open the clamping barsbefore releasing gaspressure in the water chamber, as when refilling the generator, a smallrecess N is made in the bar 11 or the bar 12 or in registration in bothbars midway between their end portions on the side engaging the shield,see Fig. 7. With this recess in the bars the shield is not clampedtightly at the point of recess thus providing a passageway between thewalls of the shield by which gas from the carbide hopper may escape intothe water chamber.

It will be understood that lime from .calcium carbide, although a watertightening element, particularly when first formed, does not cake toany'ap preciable degree of thickness on the wall of a passageway forcarbide whose surface is changing at intervals. By reason of the elasticwall of the splash shield it is changed in contour near the carbideoutlet at intervals through theuse of the clamping means which, wouldshed any a preciable deposit thereon in that vicinity. esides theclamping means, the dashing of water upon the shield as when thegenerator is hauled in a motor vehicle often changes the contour of theentire shield for a short period of time thus breaking loose any limecake formed on the inner surface of the shield in use betweenhauls.Furthermore, due to the elastic wall of the shield, the wall is pressedand thereby reduced in thickness throughout its length when there is'gas pressure in the generator. Upon releasing gas pressure as whenrefilling the generator the wall of the shield returns to normalthickness which would loosen any lime cake formed on the inner surfacethereof between fillings. Thus it will be seen that the inner surface ofthe splash shield is changed in various ways through the use of thegenerator and is therefore self cleaning.

Referring to Fig. 8, numeral 1 designates the water chamber of anacetylene generator; 2, the carbide hopper; 3G, the hopper bottom whichin this style of generator is made integral with the carbide hopper; 7B,the

carbide feed valve; A, the splash shield which in this generator hasplain ends, being cut the desired length from soft rubber tube stock.The upper end of the water chamber terminates in a short cylindricalmouth-piece 1C, having comparatively thick side walls and a smooth androunded upper edge or rim. Through this mouthpiece the splash shieldextends downwardly into the water chamber to a short distance above thewater level. The upper end of the shield being stretched outwardly overthe rim and downward upon the outer side of the mouth-piece whereupon itcontracts when released, holding itself in place. The lower end of thecarbide hopper terminates in a short tube 21, having an outside diameterof such size as will fit into the end of the shield. A second short tube22, whose inside diameter is of such size as will receive themouth-piece with the shield in place, is made integral with the carbidehopper about the tube 21 thus formment of gas at the rim of themouth-piece. Stud bolts 1H, extending upright from the water chamberthrough eye projections 2X, on the hopper extension 22 serve with thenuts lY, for clamping the carbide hopper onto the water chamber. Thesplash shield in this generator is without clamping means on account ofthe generator not being intended for extensive portable use. In haulingthis generator on a hand truck in and about the shop there isoccasionally some splashing of water upon the outer wall of the shield,mostly upon the lower end which, would cause some agitation in the wallof the shield. And if the generator be tilted to the side as in haulingit over irregular surfaces the wall of the shield would be changed incontour for a short period of time by gravity, thus sheathing limedeposit which may have formed on the inner surface of the shield. Whenthere is as much as five pounds variation in gas pressure in thegenerator there is a slight variation in thickness of the wall of theshield which goes to prevent the caking of'lime on the inner surfacethereof.

Referring, to Fig. 12, numeral 3 designates a separable hopper bottomwhich may be used in a stationary generator of a style similar to thatshown in Fig. 1. The drip ring AB, is the same as the splash shieldexcept it is shorter and, may be secured to the hopper bottom thesame asthe splash shield shown in Fig. 6. And it may be cut to the desiredlength from suitable rubber tube stock. This drip ring prevents theformation of lime cake on the inner surface thereof by changing in wallthickness due to variation in gas pressure in the generator, as for aninstance, when the pressure is released to refill with water andcarbide. I

Referring to Fig. 13, the drip ring AC, consists of a suitable length ofsoft rubber tube stock having a margin adjacent its ends cemented, thenthe tube is'doubled back u on itself bringing the cemented ends toget erto be heat treated. The space X, between the two walls of the ring maybe filled with an elastic material such as air, soft rubber strands, acoil of small soft rubber tubing or rubber sponge material, not shown,the filler being inserted before the cemented marginal ends of thecasing are cured together. The vulcanized end ring thus formed may beclamped on to the hopper bhttom in a manner similar to that shown inFigs. 6 and 12. This cushion drip ring, as it might becalled, has someadvantage over the plain ring in that it has greater contraction undergas pressure and therefore greater expansion upon releasing gaspressure. Thus the resistance against lime caking on the walls of thering is greater. This form of my invention may be used ingeneratorshaving the major portion of the carbide hopper extending downinto the water Y, of the drip chamber. Such hoppers have more exposedsurface which condenses more moisture, consequently there is more dripat the drip ring.

It will be seen that by preventin r lime deposit on the inner surface ofthe s ield also prevents moisture being drawn up into the shield or dripring and into the carbide feed outlet by capillary attraction throughthe pores of the deposit.

While I have shown and described a variety of splash shields and driprings constructed in accordance with my invention, it will be manifestto persons skilled in the art that many changes may be made in minor detail of structure in adapting the device to various use, and slightchanges in the mode of operation of same within the scope of theappended claims, without departing from the spirit of the invention; itis, therefore, to be understood that this invention is not to be limitedto the details described and shown.

What I claim is 1. In a valve shield for the valve controlled carbidefeed outlet of a carbide feed hopper mounted on the water chamber of anacetylene generator, a flexible tube depend ent from about said outlet,means for clamping said tube laterally and closing it adjacent to saidoutlet.

2. A tubular carbide feed shield having an inner wall impervious toacetylene and water moisture under generator pressure and inherentlyunstable in wall thickness and wall surface at substantial variation ingenerator pressure, an outer wall, and an enclosed cavity between thewalls.

3. In an acetylene generator having a wa ter chamber and a'carbide feedhopper with a valve controlled carbide feed outlet mounted on the waterchamber, a vertically disposed tubular shield dependent from about thecarbide feed outlet, said shield having an inner and an outercircumferential wall impervious to acetylene and water moisture unergenerator pressure forming a sealed annular enclosure, elastic materialin said enclosure, the inner wall of the shield being elastic to beexpanded and compressed with said enclosed elastic material by gaspressure in the generator and to return to normal size and thicknesswhen gas pressure in the genmaterial impervious to water moisture undergenerator pressure dependent from said annular shoulder and extending asubstantial distance downwardly into the generator chamber, includingannular elastic means constantly tending to retain the valve membercylindrical, and annular clamping means for securing the valve memberonto said shoulder.

5. In a portable acetylene generator having a water chamber and acarbide feed hopper with a valve controlled carbide feed out let mountedon the water'chamber', a valve splash shield for the carbide feed outletdesigned to be closed when the generator is hauled about, adapted toprevent water splashing into said carbide feed outlet and also toprevent water running into the carbide container through said outletshould the gen-f erator be accidentally overturned in hauling,

consisting of a vertically disposed tube of resilient material dependentfrom about said carbide feed outlet and extending a substan tialdistance downwardly into the generator chamber, and means for grippingand closing the tube immediately under the carbide feed outlet, saidgripping means being manually operated to grip and release said tubethrough the medium of a connection with a rock shaft terminating in ahandle on the exterior of the generator.

6. In a portable acetylene generator having a water chamber and acarbide feed hopper with a valve controlled carbide feed outlet, avertically disposed tubular splash shield de pendent from'about thecarbide feed outlet and extending downward into the water chamber of thegenerator, said shield having an elastic and flexible wall impervious towater moisture under generator pressure.

7. .In a portable acetylene generator, a tubular carbide feed passagewayof elastic material imperviousto water moisture under generator pressureextending from about the Y carbide feed outlet downward into the waterchamber, said passageway designed to protect the carbide feed outletfrom splashed water in the chamber, the lower edge of said passagewaybeing free to swing laterally upon tilting the generator. v

8. A generator comprising a container, a hopper mounted in the upper endof the container and provided with a depending apron, a flexible skirtconnected to the apron and depending therefrom and having the free endthereof freely movable in the container to prevent liquid in thecontainer from splashing into the hopper, the bottom of the'hopperhaving a discharge opening embraced by th'e skirt, a "alve for closingsaid opening.

HERBERT G. IRWIN.

